Fever/blood pressure spikes/red "splotches" sporadic on face/ears/neck/chest/arms. now maybe herpangina in mouth? other possible cause?

Viral illness: Everything you've described could all be caused by a viral illness. Are you around children? Or other folks who have been sick or, perhaps, stayed home from school or work now? If you're not improving in a day or so, you should seek attention for a possibly more serious infection.

HFMD?: Hand, foot, and mouth disease (hfmd). Its caused by viruses that belong to the enterovirus group. This includes polioviruses, coxsackieviruses, echoviruses, & enteroviruses. Signs are fever, blister-like sores in the mouth (herpangina), & a skin rash. If it is painful to swallow, drink liquids to stay hydrated. Take otc tylenol (acetaminophen) for fever, Ibuprofen for pain/swelling. And see an md to be sure!

Allergic reaction: You could be allergic to medication, food, perfume, something in soap or lotion. See physician.